Pictured: Moment reclusive To Kill a Mockingbird author Harper Lee sees the cover of anticipated second novel for the first time - as fans and critics rush to give their verdict after release of first chapter

Lee, 89, was pictured at an event in her hometown of Monroeville, Alabama

The Pulitzer Prize-winning author has not been seen in public since 2009

First chapter of Go Set A Watchman is printed in some newspapers today

It follows grown-up Scout as she travels to Alabama to meet Atticus, 72

Harper Lee has made her first public appearance in six years - just days before the highly anticipated release of Go Set A Watchman, the unexpected follow-up to her 1960 classic To Kill A Mockingbird.

The novel, which will hit shelves on Tuesday, is being hailed as the biggest book launch in recent memory - having already amassed as many pre-orders as the record-breaking Harry Potter series on Amazon.

The first chapter was published in some newspapers this morning and reveals how Scout, the tomboy heroine of To Kill A Mockingbird, is now an adult and travelling to Alabama from New York, where she resists the marriage proposals of one of Maybomb's finest men.

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Rare appearance: Harper Lee (center) and close friend Joy Brown (right) are shown a copy of Go Set A Watchman by documentary maker Mary McDonagh Murphy in Monroeville, Alabama, on June 30

Her lawyer father Atticus is now 72 and increasingly frail but refusing to give up practicing law. And in a shocking moment to 'Mockingbird' fans, it is casually revealed that Scout's brother Jem has 'dropped dead' in his tracks.

Critics have given their opinion on the opening chapter of the book, which were released to The Guardian and New York Times on Friday.

Reviewer Alexandra Alter wrote that while the 'flawed' book shares 'literary DNA' with To Kill a Mockingbird, it is clearly going to develop into a very different story

Cover: Go Set A Watchman will be out on Tuesday

'Whether or not it holds up to (Lee's) Pulitzer Prize winning novel, 'Watchman' will offer readers an unprecedented and unfiltered look into the mind and creative process of one of the country’s most revered and enigmatic authors,' she wrote in the New York Times.

Despite being written in the 1950s, the contents of the novel have been a fiercely guarded secret for more than 60 years after Lee was asked to put the manuscript to one side by her editor - leading to questions over when it was deemed 'unpublishable' in the era it was written.

Pictures have now emerged of Lee, 89, at an intimate lunch thrown in her honor at the Prop & Gavel restaurant in Monroeville, Alabama - her home town. At the June 30 event, she was shown the hardback copy of Go Set A Watchman for the first time.

According to People, it is only the second public appearance the reclusive writer has made since 1964.

Lee's literary agent Andrew Nurnberg said she was in a 'good mood' when she was presented with her book.

'She knew she was going to see these copies and was getting keen to see the book out there, finally', he told The Guardian.

'When I told her how many copies they were printing she was completely shocked because this is a book she had been advised to put on the back burner.'

THE OPENING SCENES OF GO SET A WATCHMAN

In the first chapter of Harper Lee's second published novel we meet Jean Louise Finch - aka Scout - as she travels back to her home state of Alabama from New York to visit her ageing father, Atticus.

Disembarking at Maycomb she looks for her father who is not there, as expected, to meet her. Instead, she meets Henry Clinton, who grabs her in a 'bear hug' and 'kissed her hard on the mouth, then kissed her gently.'

Clinton, we learn, is a 'comrade' of her brother Jem and a potential husband for Jean. During a playful exchange as they drive away from the station, she rejects his marriage proposal despite there being 'no finer man' in Maycomb.

He worked for Atticus, who is increasingly suffering with rheumatoid arthritis. Atticus took Clinton under his wing after Scout's brother Jem 'dropped dead in his tracks.'

The chapter ends with Scout apologizing for upsetting Clinton during the car journey as she ponders silently whether she could be his wife.

The photo was released by filmmaker and author Mary McDonagh Murphy, who in 2012 made the documentary Harper Lee: Hey, Boo.

An updated version of the film, renamed Harper Lee: American Masters, will air in the U.S. on PBS on Friday night.

The moment at the restaurant was reportedly filmed and will feature in the updated documentary tomorrow.

Also there was Joy Brown, Lee’s close friend and benefactor, Deadline reported.

Lee Sentell, director of the Alabama Tourism Department who was at the lunch last week, told The New York Times that Lee rejected widely held beliefs that the book was being printed without her expressed consent.

'Of course I did (give my consent), don't be silly,' Lee said, according to Sentell.

It may very well be the only outing Lee makes ahead of the release of the novel, which has been mired with controversy since publisher HarperCollins confirmed it in February.

The announcement came just three months after the death of Lee's older sister, lawyer and gatekeeper, Alice Lee.

Harper and Alice lived together at a nursing home in Monroeville, where Harper continues to reside.

Alice was 103 when she died on November 17.

Lee once described her sister as 'Atticus in a skirt', referring to her beloved Mockingbird character Atticus Finch, who was believed to have been inspired by their father.

The new novel is first book Lee (pictured in 2001) has released since her 1960 classic To Kill A Mockingbird

GO SET A WATCHMAN: CRITICS AND FANS OFFER THEIR FIRST REVIEWS

While critics were qualified in their praise of the first chapter, reaction among fans was largely centered on the anguish at finding out that Jem, a treasured character from 'Mockingbird', had been killed off.

Guardian Books editor Claire Armistead told BBC Radio 4 that while it was 'really difficult' to say how the rest of the book would read, she found the first chapter of Go Set A Watchman 'promising'.

'What it sets up is lots of fascinating scenarios,' she said.

'The childhood friendships have gone... Obviously Scout has a romantic association with the black community which I suspect is going to really develop.

'It has also got a nice line in irony. It has this line: "Recorded history’s version does not coincide with the truth, but these are the facts, because [they were passed down by word of mouth through the years] and every Maycombian knows them."

'So it is sort of setting up the idea of a reality that doesn’t accord with the facts. And I think it is actually really promising.'

Readers took to Twitter to express their dismay that Jem had been killed off in the years between the setting of 'Mockingbird' and Go Set A Watchman.

Others enjoyed the book more. Alexander Woolf wrote on Twitter: 'The first chapter of the new Harper Lee book is wonderful! "If you did not want much, there was plenty." Beautiful.'

Kieron Butler said: 'Well, the first chapter of #GoSetAWatchman has me hooked. Beautiful to read, funny and profoundly moving.'

Reviews from the public: Most reacted positively to the first chapter, although some expressed dismay that Jem had been killed off

Lee retreated into an intensely private life following To Kill A Mockingbird and repeatedly refused to publish another novel for more than 50 years.

Some in Monroeville subsequently question whether she was capable of consenting to the second novel's publication.

A longtime friend came forward claiming Lee is mostly deaf, blind and in poor health.

Others questioned whether her mental health was sound enough to make such a decision.

However, after launching an investigation, Alabama Securities Commission Director Joseph Borg said earlier this month that his agency reviewed the matter at the Department of Human Resources' request, and that Lee answered questions to an investigator's satisfaction.

The case was then closed.

The Times reported that investigators interviewed staff at The Meadows assisted living facility where Lee resides, as well as friends and acquaintances.

A doctor who asked to remain anonymous said he had filed a complaint after knowing Lee for two years and believing her infirm.

He said he had been told she was mostly incapable of communication.

Such investigations can involve law enforcement if financial exploitation can be shown.

Actor Gregory Peck and novelist Harper Lee on the movie set of To Kill A Mockingbird in 1962

One person speaking to The Times anonymously said Lee seemed to understand the investigators and give clear responses.

People have argued for several different pictures of Lee: funny, depressed, witty, confused and even varying from day to day.

Lee was last seen at the Alabama Academy of Honor Inductions in October 2009 (pictured)

She reportedly had a stroke in 2007, resulting in health and vision problems.

'It's a call only God or a doctor can make,' said attorney Philip Sanchez, who was a pallbearer for her older sister Alice's funeral. 'I am more concerned that Nelle (his name for Harper) is content than the discussion of her cognizance.'

Accounts of Lee's mental and physical state have been contradictory over the last few years, but intensified recently after HarperCollins announced her second book, Go Set a Watchman

A friend of Lee, Wayne Flynt, said he visited her recently and found her mentally cogent.

But he agreed she had some health issues, and said she told him: 'I'm not so sure any more,' in response to a congratulations on the new book.

Lee has only given statements about the novel through her attorney, Tonja B. Carter.

Carter handled the book deal and declined to respond to interview requests.

Lee wrote the book, Go Set A Watchman, in the 1950s.

It was submitted to publishers before To Kill A Mockingbird and is considered her earliest work.

The manuscript was presumed lost, according to reports, but was found last year in a safety deposit box, alongside the original Mockingbird manuscript.

Investigation: Earlier this year, staff at The Meadows assisted living facility where Lee resides in Monroeville, Alabama, were interviewed to see if she was mentally fit

It centers around Mockingbird's protagonist, Scout, returning to the fictional of Maycomb after 20 years.

On Thursday, Amazon announced that Go Set A Watchman was already the best-selling book on the website.

It is the most pre-ordered book on Amazon.com since J.K. Rowling's Harry Potter and the Deathly Hallows in 2007 - the seventh and final novel about the British teenage boy wizard.